The figure has led to concerns that local government is using devolution to seize power rather than actively engage local people and organisations in redesigning public services.

"If devolution just centralises power in town halls, then we’re destined to continue the disillusionment and disengagement of old," said Karl Wilding, director of public policy at the NCVO.

Wilding described devolution as a missed opportunity so far. He said it needed to be more transparent and collaborative, and urged councils to make greater efforts to involve voluntary organisations.

"We are also concerned that the current focus on economic development comes at the expense of public service reforms, meaning some of the potential for reshaping services around community needs and assets is lost," he said.

"The Prime Minister has been clear that she expects the state to do more to work with the voluntary sector as part of her shared society vision."

There are currently no published criteria on how councils should make devolution deals.

The NCVO calls for the introduction of minimum standards of engagement with charities and other local stakeholders as well as plans showing how the voluntary sector will be involved.

But the report also urges charities to be proactive. "It is no good sitting back and waiting for local authorities to come to them," it says.

It urges local charities to consider collaboration and merger as ways of influencing the devolution agenda.

Mayoral elections are due to take place in six combined authority areas on 4 May: Cambridgeshire and Peterborough, Greater Manchester, Liverpool City Region, Tees Valley, West Midlands and West of England.

The Department for Communities and Local Government declined to comment.

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